Most women are too hard on themselves when it comes to cardio. But when it comes to weight training, they might very easily be going too easy on themselves.

Studies show women tend to lift weights that are too light because they are afraid they'll bulk up. But that's not the case. Women generally do not produce enough testosterone to build bulky muscles. And if the weight isn’t heavy enough, it won’t provide enough resistance for your muscles to make gains in muscular endurance or strength, which makes lifting weights completely pointless.

Experts recommend that you start with a 10-pound weight, which is light enough to avoid injury, and see how many repetitions you can do of a certain exercise (like an overhead press or biceps curl). If you can easily do more than 15 repetitions at that weight, you should increase the weight by 5-10 pounds and repeat the drill. Do this until you figure out how much you can safely lift in 8-12 repetitions, which is the preferred amount of reps for improving muscular endurance.

Once you’ve found a weight that challenges you, stick with it until it also becomes too easy. Then, increase the weight by 5-10 pounds again until you find a comfortable but challenging weight. Muscular adaptations can occur in as little as a few sessions or a few weeks of training, so don’t be surprised if you have to increase weights a lot in the first few months of training.